5.56x45 M855

[ASP785]

I have attached a couple of photos illustrating an issue I recently had with some 2011 manufactured M855. The photos show severe bullet setback in the case upon chambering the round. There is a round of M193 shown for comparison purposes only. Fortunately for us, this caused a stoppage in the weapon. Had it fully chambered and fired the results may not have been good. The case mouth shows the typical 'grooves' associated with a case that has been crimped to a bullet's cannelure. I can only guess that the neck was not properly sized and that the crimp was not applied strong enough to fully keep the bullet in to place.

 

[KilkennyArms]

It almost looks like a blank but of course not quite. It is not uncommon for the manufacturer to decide that an entire batch is not suitable to ship so they pull apart the bullets and scrap the batch. Where did you buy these?

 

[crispy]

ive seen this a few times. what causes this?

 

[aeropb]

Just suffered a feed jam

 

[ck0s99]

That's happened to me when my weapon was running dry. Oiled her down and problem solved not so sure in your case tho.

 

[ASP785]

The cause of the malfunction was the bullet set back and not the other way around. The ammo is XM855 that was purchased from a retailer locally. It came in a sealed ammo can 420 pieces on 10 round stripper clips. From the responses it seems this is common, which both is a shame and surprises me. Ive loaded thousands of rounds of 223 over the last few years and never experienced this issue....malfunction or no malfunction.

 

[oneof79]

With pistol ammo, if you chamber the same round more than a few times this is a real possibility. The way the front of the bullet is scratched up it kind of looks like it may have been chambered and manually ejected several times.

 

[SMS]

Is this U.S. factory manufactured M855 or remanufactured/reloaded M855?

 

[Boehlertaught]

Certainly each round can't take a constant dose of chambering and ejecting. But, with a proper crimp, would not the round be OK?

 

[ASP785]

It is Federal Lake City XM855, First run, first quality. Anything labeled under the Federal banner "XM" is first quality and not reloads or rejects. You can re-chamber a round in an AR without any bullet setback with proper neck tension and crimp. The problem is with the AR's free floating firing pin. With repeated chamberings, the firing pin actually lightly taps the primer each time which can crush the primer compound. This can create a "click" instead of a "bang". That is why if you a carrying your rifle to defend your life, you never want to re-chamber a round unless it is for training purposes only.

I posted this simply for illustrative purposes. Federal, one of the best (if not the best) domestic producers of ammunition, even has a bad one every now and again. The round in question was only chambered once and the paint scratches are from removing the stuck round from the chamber.